Cleanrooms are demanding environments with stringent atmospheric requirements for safe and effective work in industries as wide ranging as pharmaceuticals, scientific research, and microchip manufacturing depending on atmospheres with sharply limited contaminants. To achieve that, cleanrooms have to follow exacting standards and have unique safety challenges.

1. Cleanroom Classifications and Testing

The first and most important aspect of cleanroom safety is ensuring an environment with extremely limited contamination. This requires meticulous testing and an understanding of what cleanroom classification is required. The standard is set by the International Organization for Standardization (ISO), which determines cleanliness with a system of nine classification levels. Measuring this requires testing the count of particles in your cleanroom, with the number of sample locations based on its size. ISO 1 is the cleanest possible level, where a sample must have 10 or fewer particles measuring 0.1 microns and only 2 or fewer particles at 0.2 microns. ISO 9 is an average room’s air.

2. Guarding Against Contaminants

Ensuring a sterile environment requires specialized equipment and numerous safety measures. Some of these are room design elements, like sealed environments, pass-through doors that reduce traffic into the room, gowning rooms for safely putting on or removing sterile clothing, point-of-entry air showers, or particulate-capturing sticky mats. It will also encompass environmental systems like atmospheric controls, air filtration systems, and fire suppression systems. Other measures are for employees, such as disposable personal protective equipment (PPE) or personal respirators such as self-contained breathing apparatuses (SCBAs).

Understanding air change rates – the number of times per hour air passes through a filtration system – and the rates required for your cleanroom is another necessary aspect of protecting against airborne particulates.

3. Hazardous Materials Guidelines

It’s worth remembering that while the cleanroom designation is for unwanted contaminants, hazardous substances or dangerous materials may be a factor in a cleanroom. For instance, in semiconductor manufacturing, which requires stringent cleanrooms, hydrofluoric acid is used for fabricating circuits and etching semiconductors. Knowing specific restrictions on hazardous materials like this is important, such as the provisions in the Occupational Safety and Health Administration’s (OSHA) 29 CFR 1910.1450 requirements for toxic chemicals in laboratories. These regulations require laboratories to practice strict hazard identification and labeling, as well as provide no-cost respirators to employees among other guidelines; for certain materials these provisions can supersede OSHA’s general rules about hazardous substances.

Gas sampling is also a regular occurrence in many cleanroom settings, which means that regulations about compressed gas cylinders apply, including provisions for secure storage and movement to prevent cylinder damage and leaking, as well as fire barriers and distance from heat sources.

4. Hazard Identification and Management

Keeping your cleanroom safe starts with identifying hazards, including within safety elements. Air filtration systems need regular inspection and maintenance; a sealed room with sharply limited access can endanger people when evacuation is necessary. An inventory of potential hazards is a great place to start making a plan for managing cleanroom safety that incorporates numerous safety best practices and compliances.

• A written safety policy with a clearly established chain of command and reporting process for incidents and non-compliance
• Workflow maps for the working area as well as entry and exit procedures
• Worker education and training in all relevant compliance standards
• PPE distribution to employees, including safe storage and disposal
• Regular airborne particulate testing
• Inspection and maintenance policies and schedules, especially for air filtration systems
• Monitoring and alarm systems for air quality and other potential hazards